Azadirachta indica cell suspension culture can be used for the biotransformation of dianabol (Compound 1) to yield metabolites including 17β-hydroxy-17α-methyl-5α-androst-1-en-3-one (Compound 2), and 17β-hydroxy-17α-methyl-5α-androstan-3-one (Compound 3); these can be alternately synthesized chemically. The structures of these compounds were deduced on the basis of various spectroscopic techniques.
Compound 2 exhibited a significant immunomodulatory inhibitory activity and strongly suppressed the PHA-activated T-cell proliferation (IC50: <10.33 μM) comparable to control drug prednisolone, after 72 hours incubation, and was further found to interfere with the IL-2 production (IC50: 16.89±1.32) (FIG. 2A). Compound 2 also exhibited anticancer activity against lung cancer cell line; NCI-H460, it moderately inhibited the growth of cancer cells (22.5±4.15 μM).
Compound 3 exerted a moderate inhibitory activity on both tests as compared to Compound 2. On the other hand, the Compound 1 did not show any significant effect on the tested system.
Molecular docking studies were also performed to speculate possible interaction among IL-2 protein, and biotransformed products; studies exhibited a good correlation between the predicted binding energies of the compounds acquired by the FlexX program and the experimental affinities. For docking studies, crystal structure of human IL-2 complexed with Compound 4 [(R)—N-[2-[1-(aminoiminomethyl)-3-piperidinyl]-1-oxoethyl]-4-(phenylethynyl)-L-phenylalanine methyl ester] was downloaded from Protein data bank (pdb id: 1M48).